Progress bar not displaying while using fileupload in ajax

Hi sir,
 I used fileupload control inside the ajax updatepanel, progress bar not displaying while uploading. In my project , i uploaded excel file, and read the contents and insert into database. My problem is, progress bar not displaying while upload operation, it takes 2 mins to complete the entire process of uploading work. I shared the code for your reference. Kindly give me the solution for this problem.

Code:

<div>
        <asp:ScriptManager ID="ScriptManager1" runat="server">
        </asp:ScriptManager>
        <asp:UpdatePanel UpdateMode="Always" DisplayAfter="0" ID="UpdatePanel1" runat="server">
        <ContentTemplate>
          <table align="center">
            <tr>
                <td>
                    <asp:Label ID="Label1" runat="server" Text="Please select the file"></asp:Label>
                </td>
                <td>
                    <asp:FileUpload ID="FileUpload1" runat="server" />
                </td>
                <td>
                    &nbsp;</td>
            </tr>
            <tr>
                <td>
                    &nbsp;</td>
                <td>
                    <asp:Button ID="btn_upload" runat="server" onclick="btn_upload_Click"
                        Text="Upload" />
                </td>
                <td>
                    &nbsp;</td>
            </tr>

        </table>

        </ContentTemplate>

        <Triggers>
         <asp:PostBackTrigger ControlID = "btn_upload"  />


        </Triggers>

        </asp:UpdatePanel>
    <br />
        <asp:UpdateProgress AssociatedUpdatePanelID="UpdatePanel1" DynamicLayout="true"  DisplayAfter="0"  ID="UpdateProgress1" runat="server">
        <ProgressTemplate>



         <div id="overlay">

                <div id="progressone">

                    <div id="progresstwo">

                        <img src="images/loading.gif" alt="" />

                    </div>

                </div>

            </div>


        </ProgressTemplate>
        </asp:UpdateProgress>

    <br />